Free Sidechain Compression Timing Calculator

How to Use This Calculator

Set your BPM with the slider, number box, tap tempo, or one of the genre presets — 124 for house, 128 for techno, 140 for dubstep, 150 for trap, 174 for drum and bass. The three result cards update instantly: Attack stays fast and fixed (you rarely need to touch it), Hold gives a short window before the release kicks in so the initial transient isn't swallowed, and Release is synced to whichever note value you pick from the dropdown. Tap any of the three values to copy it straight to your clipboard, ready to paste into your compressor plugin.

Unique Feature: Voice Feedback

Flip on Voice Feedback and the calculator reads out attack, hold, and release the moment you tap a value. Handy when you're leaning into a hardware compressor or a plugin with tiny knobs and don't want to keep glancing back at a browser tab to double-check a number.

Why Sidechain Timing Actually Matters

Sidechain compression is everywhere in dance music now — that pumping sound where a bass or pad audibly ducks every time the kick hits. It's easy to get the ratio and threshold roughly right by ear, but timing is where most home productions fall apart. Set the release too fast and the pump barely registers before it snaps back, sounding twitchy rather than groovy. Set it too slow and the bass never fully recovers before the next kick lands, so the low end just gets quieter and quieter until it's mush. Locking release to an actual note value at your BPM is what turns a vague "duck" into a pump that breathes exactly in time with the track.

Attack, Hold, and Release — What Each One Actually Does

Attack is how fast the compressor clamps down once the kick triggers it. For sidechain work this almost always wants to be near-instant — 0-2ms — so the kick punches through cleanly instead of getting compressed along with everything else. Hold is a less common parameter, but where a compressor offers it, a short 5-15ms hold keeps the gain reduction pinned at its deepest point for a beat before the release phase begins, which stops fast transient material from sneaking back up too early. Release is the parameter doing the real musical work — it decides how long the ducked element takes to climb back to full volume, and syncing that duration to a note value at your track's BPM is the whole trick behind a pump that feels intentional rather than random.

Genre Reference: Typical Sidechain Settings

These are starting points, not rules — plenty of great records break them on purpose. But if you're not sure where to start, matching the table above will get you close on the first try.

A Few Things That Trip People Up

The most common mistake I see mentioned in producer forums is chasing release time while ignoring threshold and ratio — timing only controls the shape of the duck, not how deep it goes. If the pump still sounds weak after dialing in a tempo-synced release, the problem is usually threshold sitting too high, not the millisecond value being wrong. Another one: forgetting that "quarter note" doesn't automatically mean "correct." A track built around a half-time feel — a lot of modern dubstep and some trap — often needs release synced to double the note length you'd expect from the raw BPM number, or the duck will resolve mid-beat instead of on it. When in doubt, solo the sidechained element and listen for whether the volume fully recovers right as the next kick lands; if it recovers early, lengthen the release, and if it's still ducked when the kick hits, shorten it.

Who This Is Actually For

Mostly bedroom producers working in house, techno, and dubstep, honestly — that pumping bass sound is basically a genre signature in EDM at this point, and nailing the timing is what separates a track that sounds professional from one that just sounds "compressed." Mix engineers use the same math when they're gluing a mix together with a bus compressor keyed off the kick, even outside strictly electronic genres — a subtle, tempo-synced pump can add cohesion to a pop or rock mix without anyone consciously noticing it's there. Live sound and broadcast engineers occasionally reach for the same formula too, ducking music under a voiceover in time with the beat rather than just slamming the volume down.

When to Trust the Number vs Your Ears

A calculated release time is a starting point, not gospel — I'd treat it as the value you set before you start listening critically, not the value you leave it at no matter what. Once it's dialed in, solo the sidechained track against just the kick and listen through a full 8 or 16 bars. If the pump feels mechanical or too obvious, nudging release 10-20% longer or shorter than the "correct" mathematical value often sounds more musical than the exact number, especially once other elements are layered in and masking some of the effect. The calculator gets you in the right neighborhood instantly instead of guessing from scratch; your ears still get the final say.

Frequently Asked Questions

What attack time should I use for sidechain compression? Almost always as fast as your compressor allows — 0 to 2ms. Attack isn't usually the parameter you tune for the pumping effect; that's release.

How do I calculate sidechain release time from BPM? Divide 60,000 by your BPM to get a quarter note in milliseconds, then adjust to a different note value if you want a faster or slower pump. This calculator does that instantly for any BPM and note value.

Should release always match a quarter note? No — quarter note is the most common starting point for house and techno, but faster genres like drum and bass usually need a shorter subdivision like a sixteenth note so the pump resolves before the next kick.

What's the difference between this and a delay time calculator? Same underlying math (60,000 ÷ BPM), but applied to compressor envelope timing instead of delay/reverb effects. If you need delay or reverb pre-delay values too, our Delay Time Calculator covers that separately.